This invention pertains to a window hinge for mounting a window sash for pivotal movement between open and closed positions and which utilizes a track mountable to a window frame and a sash arm mountable to a window sash. Pivoted links and associated structure mount the sash arm to the track and provide for movement of the window sash. The sash arm is positioned opposite the track when the window is closed with the inside edge of the sash arm aligning with the inside edge of the track to assure tight closing of the window.
A window hinge of the general type disclosed herein is well known in the art, with applicant's assignee having a commercially-available 6-bar hinge having a track mountable to a window frame, a sash arm mountable to the window sash, a shoe slidable on the track, and a series of links pivotally interconnecting the sash arm to the shoe and the track to enable pivotal movement of a window. Additionally, the track has an inverted V-shaped cam at an end thereof and the sash arm has a cam surface at an end thereof for coaction with the cam member to assure movement of the window hinge and the window sash to a fully-closed position. When the window is closed, the outside edge of the sash arm is aligned with the outside edge of the track.
Additionally, window hinges of the general type disclosed in this application are shown in the Anderberg et al U.S. Pat. Nos. 2,784,459 and 3,345,777. These patents disclose a track with a V-shaped cam member at one end mountable to a window frame and a sash arm mountable to a window sash, with the track movably mounting a shoe and a series of links pivotally connecting the sash arm to the track and shoe. The first-mentioned Anderberg et al patent shows and describes the coplanar relation of the various pivot connections between the window hinge components and the lateral offset of certain of the pivotal connections when a window is fully closed. This results in the outside edge of the sash arm being in alignment with the outside edge of the track member. As pointed out in the patent, this offsetting of certain pivot connections to either side of the median line of the track results in the ability to use identical supporting brackets or window hinges at each end of the window merely by shifting the bar 16 (sash arm) to either side of center to predetermine to which side of the track the bar and associated connecting members are to move.
There are certain applications which require that the window hinge have the sash arm inside edge aligned with the inside edge of the track to fully close the window and the invention disclosed herein achieves this result.